1. Field of the Invention
The present invention concerns a portable mobile radio transceiver, especially for direct communication with a radio relay station on a satellite, the transceiver including a casing provided with a microphone and an earpiece and an antenna mounted on the casing.
2. Description of the Prior Art
The casing of a transceiver of this kind is generally elongate in shape and its configuration is similar to that of portable terminals for terrestrial mobile radio networks. The casing is primarily intended to be used held in the hand in a position such that the earpiece is near one ear and the microphone near the mouth of the user. In some implementations the casing can also be placed on a support, enabling "hands-free" use of the transceiver.
These transceivers usually have an elongate whip or telescopic type antenna fixed to the casing so that it projects from the latter, being aligned with it in its longitudinal direction.
In the case of portable terminals for direct communication with a satellite the electromagnetic field levels are relatively low and it has been found that a configuration of these transceivers similar to those used in terrestrial mobile radio networks is unsatisfactory.
An object of the invention is to provide a mobile radio transceiver of the above-mentioned type procuring significantly improved transmission and reception. In this regard, it has been found that the radiation diagram of the antenna can be optimized, in particular by a geometrical displacement of the diagram relative to that obtained with the usual configuration.
The invention is further directed to providing a transceiver of this kind which can be held either in the left hand or in the right hand, or mounted on a desktop stand if required.